A. Field of the Invention
The present invention relates to collagen covalently bound to particles, which results in a material that is more resistant to degradation such as collagenase degradation. This material can be used in a wide range of applications.
B. Description of Related Art
The use of collagen in treating urinary incontinence, post heart-attack congestive heart failure, joint fractures, and congenital and age-related facial skin defects is limited by the stability and integrity of the currently available collagen materials. For example, collagen-based dermal fillers that are used to treat facial ageing (e.g., improving facial contours, ameliorating wrinkles, correction of scar depression, etc.) and to augment lips are highly susceptible to breaking down over a period of 12 months.
One proposed solution to the collagen breakdown issue is crosslinking collagen by the formation of covalent bonds between macromolecule collagen fibrils. However, the toxicity of the chemicals utilized to crosslink collagen can be a concern. For example, glutaraldehyde and hexamethylene diisocyanate become incorporated within the collagen scaffold during crosslinking and can release toxic residues into the body as the collagen is degraded. Another problem is that too much cross-linking can create a stiff and unusable collagen material.